Abstract
The GOES N-Q (13-15) imagers built by ITT EXELIS have an improved optical design that allows them to view the Sun directly without safety concerns. However due to significant stray light before and after eclipse periods, data around local midnight was previously not taken when the Sun was within 6o of the Earth disc (and not eclipsed). ITT EXELIS & NOAA/NESDIS have developed a stray light removal algorithm for all imager thermal channels, which can correct data as close to 1o from the Sun to an RMS error of less than 2K (for a 3.9μm 300K scene, the error is much smaller for other channels in most cases). The process has been designed to be run on a line by line basis in the NSOF ground system processing of GOES 13 data into GVAR counts (radiance) prior to transmission. It was activated on Feb 21st 2012 and this presentation gives the first results from EXELIS/NOAA and the general user community. This gives the USA the unique capability to monitor weather & climate at any time and on every day of the year. It is also applicable to all imagers on existing and future geo-stationary platforms (i.e. MSG, MTG, MTSAT-2, COMS-1, GOES-R (ABI) & AHI). For a demonstration of the process go to: https://sites.google.com/site/exelismatthews/ExelisGOESstraylightcorrectionpatentpending.mp4?attredirects=0&d=1
First Results from Real-time NSOF Ground System Correction of GOES 13 Imager Stray Light during Eclipse Periods
The GOES N-Q (13-15) imagers built by ITT EXELIS have an improved optical design that allows them to view the Sun directly without safety concerns. However due to significant stray light before and after eclipse periods, data around local midnight was previously not taken when the Sun was within 6o of the Earth disc (and not eclipsed). ITT EXELIS & NOAA/NESDIS have developed a stray light removal algorithm for all imager thermal channels, which can correct data as close to 1o from the Sun to an RMS error of less than 2K (for a 3.9μm 300K scene, the error is much smaller for other channels in most cases). The process has been designed to be run on a line by line basis in the NSOF ground system processing of GOES 13 data into GVAR counts (radiance) prior to transmission. It was activated on Feb 21st 2012 and this presentation gives the first results from EXELIS/NOAA and the general user community. This gives the USA the unique capability to monitor weather & climate at any time and on every day of the year. It is also applicable to all imagers on existing and future geo-stationary platforms (i.e. MSG, MTG, MTSAT-2, COMS-1, GOES-R (ABI) & AHI). For a demonstration of the process go to: https://sites.google.com/site/exelismatthews/ExelisGOESstraylightcorrectionpatentpending.mp4?attredirects=0&d=1